Process of tanning fish-skins.



no STATES r-Arnn'r orrion KRISTIAN BENDIXEN, F COPENHAGEN, DENMARK,ASSIGNOR TO KRISTIAN BENDIXEN AND PETER BENDIXEN, COPARTNERS TRADINGUNDER THE FIRM-NAME 0F SKIND- FABRIKEN UNICUM, KR. BENDIXEN, 1?.BENDIXEN AND COMPANY, OF COPENHAGEN,

DENMARK.

PROCESS OF TANNING FISI-LSKINS.

Patented Feb; 19, 1918.

Specification of Letters Patent.

No Drawing: Original application filed February 19,1912, Serial No.678,473. Divided and this application filed May "7, 1917. Seria1-No..167,154.

all whom it may concern:

To v dung and kilogram Be it known that I, KRISTIAN BENDIXEN, chemicalhating compound heated to a temsubject of the King of Denmark, andresidperature of about 18 C.

' ing at Copenhagen, Denmark, have invented After hating the skins arefirst washed m a new and Improved Process of Tanning clean lukewarmwater and then in a solution Fish-Skins, of which the followingspecifiof 3 liter of hydrochloric acid and 200 liters cation is a fulldisclosure. 7 of water.

This application is a division of my 00- The skins are then put mto avat contampending case No. 678473 filed February 19, mg a mild dilutesolution of conventional 1912 and the invention thereof relates to atanning material (about 5 or 6 barkomprocess for tanning fish skins andthe like, eter) towhich liquid a suitable tanning which process isparticularly suitable for the material is added every third day untilthe skins of sharks, porpoises, whales, etc., as it skins are thoroughlytanned. v renders it'possible to utilize and work up As an alternative,after treatment inthe such skins and thereby render themavailhydrochloric solution, the skins may e able as leather. laced in amill with about 4: kilograms T he process is as follows of salt and 40liters of water, and milled for The salted skins or hides are soaked inabout 10 minutes and then treated with three twice daily.

water until they are rendered quite sharks; these are the slm'ns howeverbeing ment in sodium sulfid and arsenic is not abskins or hides areslaked lime, and in this solutionthey-are also fresh In the case of theskins of the stretched upon frames and dried. After this the spikes orscales are removed with a clean blunt scraper or tanners knife. Theskins are next put into lukewarm water until they are rendered perfectlysoft and are then worked over a beam.

tanning material; After this the skins are again milled for about 8hours'and are then left for the night in the mill; milled again on thefollowing day for about 2 hours, and then completely tanned.

The skins after being completely tanned are next put into a mill withpure lukewarm a ain.

They are next plunged. 'nto a depilatory. water until theyare entirelyfreed from-acid, and antiseptic solution of .ZOO-liters of water and arethen milled for about 6 hours in a containing either a 'logram of sodiumsulfid -m1ld relativel dllute solution (about 5 or or a kilogramof-white arsenic-or raw, re 6 barkometerg of sumach extract-and water.arsenic, or half a kilogram of each of these. After thisthey are coloredand then smeared with oil and spread out, dried, damped and smoothedout, polished and bleached. Finally they are rubbed with one part ofalbumen and 10 parts of water or of skimmed milk to render the skinssupple and to prepare them for coloring. They are then glazed andgrained.

If the grain skins are placed for about 5 minutes in a lution of oneliter of sulfuric acid and liters of water.

In this depilatory and antlseptic solution the skins are to remain forabout three days, turned twice daily.

In the case of the skins of whales this treatsolutely necessary.

After the expiration of the three days, the put into a solution of 200liters of water and a suitable quantity of left for about three days,being again turned as examples Oakwood 0r oak-bark, or extract ofoakbark or various other extracts such as quebracho and extracts ofgambier.

' Having now described the invention, what The skins are next put into alime-neutralizing solution of 50 liters of water and '5- liter ofhydrochloric acid of the requisite strength and are agitated-for about 5mmutes in this solution to dissolve and remove as much as possible ofsuch lime as would I claim and desire to secure, 1s

otherwise remain in the pores and interfere 1,. A processfor tanningfish skins and the with the pliability of the ultimate product 3 likeconsistihg in softening the skins, treatand are then bated in a batingmill containing them for about three days in a solution ing 100'litersof water, '5, bucket of poultry of products produced by chemical actionbeof any preferred solutions of graduated strength of chrome As tanningagents the following are given I does not come outclearly, the 7 tweenwater and arsenic-and sodium sulfid, such treatments, agitating thehides for a and then treating them for a further period short while in asolution of Water and hydroof about three days ina solution of waterchloric acid, then bating them in a mill conand slaked lime. tainingwater, poultry dung and a chemical 2. A. process for tanning fish skinsand the bating compound, and then washing them in a like consisting insoftening the skins, treatpure lukewarm water andafterward with a ingthem for about three days in a solution solution of hydrochloric acidand Water. produced by the chemical action vbetween 6. A process fortanning fish skins and the sodium sulfid Water and arsenic, thentreatlike consist ng in softening the skins, treatmg them for a furtherperiod of about three mg them in a solution produced by the days ina-solution of Water and slaked lime, chemical action between sodiumsulfid, Water turning the hides during such treatments, an arsenic, thendepilating them, then bat and then agitating the hides in a solution ofing them and then milling with a suitable water and hydrochloric acid.solution of salt to which a suitable chrome f a process for tanning fishskins and the tanningmaterial is added; themilling being 1 likeconsisting 1n softenmg the skins, treatt en continued until the skinsare fully poultry dung and a chemical bating com- 8. A process fortanning fish skins and the ing them in a solution of products producedtanned, substantially as described. by chemical action between water andarprocess for tanning fish skins and the, sonic and sodium-suliid, thentreating them like consisting in softening the skins, treatbating themin a mill containing Water hing-material is added.

them in a solution of water andarsemc, then an arsenic, then treatingthem for a further sodium sulfid, Water and slaked lime, turnin ing thehides in a solution of water and hythe hides during such treatments,agitating drochloric acid, then hating the hides, then the hides in asolution of Water and hydrowashing them in pure lukewarm water andchloric acid, bating them, then removin afterward with a solution ofhydrochloric tiem into pure lukewarm Water, and then acid and water,then into a solution of hydrochloric acid and skins are fully tanned inamill containing a water. I suitable solution of'salt to which a suitable5 A process for tanning fish skins andchrome tanning material is added,then freeconsisting in softening the skins, ing the hides from acid andtreating them in treating them for aboutthree days in a solua solutionof extract of sumach and water. tion of products produced by chemicalaction he foregoing s ecification signed at 00-, between Water andarsenic andsodium sulr -penhagen,i.Denmar thisl8th day of April, fid,then treating them for a further period 917. of about three days in ,asolution ofwater and slaked lime, turning the hides during KRISTIANBENDIXEN-

